This word translated "evening" is the Hebrew word ba erev. Everybody who is a converted adult, know that days in the Bible begin and end with sunset. That is what ba erev means—"sunset." The Day of Atonement (1) begins when sunset occurs on the ninth day; and (2) it ends when sunset occurs on the tenth day! The tenth day begins at sunset (at ba erev) of the ninth! That very clearly delineates the beginning and the ending of days in the Bible—from "even to even," from ba erev to ba erev.
Ba erev means sunset. It is very specific. It includes no time before sunset. It is a period that begins whenever the edge of the sun hits the edge of the horizon. If you stood and watched how long ba erev takes, it takes about three to five minutes of time. It is very specific. We can see then, by comparing Leviticus 23:32 with Leviticus 23:27, that the Day of Atonement—the tenth day—begins at sunset on the ninth; and it ends at sunset on the tenth. (That is very similar—in fact, exactly the same—as it is with us in regard to the Sabbath. It begins at sunset on Friday evening. It ends with sunset on Saturday evening.)
This is where we ended the third sermon on this Passover series, and I want to begin here because I want this to serve as a reminder. Leviticus 23:27 and 32 clearly establishes sunset, ba erev, (Remember that word?) as the end of one day and the beginning of another.
I will remind you that the severity of punishments for breaking of the Day of Atonement were such: Verse 28: "You shall do no work."Verse 29: "The person who works shall be cut off." Verse 30: "The person who does any work in that day I will destroy." It was exceedingly important to those people (and to God) that they understood very clearly the time that they were to afflict their souls, in order that they did not get cut off. And that period of time is established by sunset(ba erev). Sunset and ba erev are one and the same thing.
So, if people were going to avoid being cut off and destroyed, they knew that when ba erev came, then the day (in this case, Atonement) was either over, or another day was beginning. Then they were free to work, or they should not work.